releasetools: Add PayloadSigner class.
Create a wrapper class that handles the payload signing, which unifies
the paths with and without external signer. Also add tests for the newly
added class.
The test keys under testdata/ are created with the script in
development/tools/make_key. testdata/testkey_with_passwd.pk8 uses
password "foo".
Test: python -m unittest test_ota_from_target_files
Test: Get identical A/B OTA packages w/ and w/o the CL.
Change-Id: Ic770aec726498a3babb88ec509985e7f1210fb18
diff --git a/tools/releasetools/testdata/testkey_with_passwd.x509.pem b/tools/releasetools/testdata/testkey_with_passwd.x509.pem
new file mode 100644
index 0000000..449396e
--- /dev/null
+++ b/tools/releasetools/testdata/testkey_with_passwd.x509.pem
@@ -0,0 +1,24 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----